PAMAM型树枝状水性聚氨酯的合成及表征

Synthesis and characterization of PAMAM dendritic waterborne polyurethane

以异佛尔酮二异氰酸酯(IPDI)、聚碳酸酯二醇(PCDL)、二乙醇胺(DEA)、蓖麻油(C.O.)、二羟甲基丙酸(DMPA)为原料,二丁基二月桂酸锡(DBTDL)为催化剂,合成了单端封闭的聚氨酯预聚体,然后将其接枝到一代树枝状大分子聚酰胺-胺(1G PAMAM)上,合成了一种新型树枝状水性聚氨酯。通过单因素分析法优化出最佳的合成条件:DBTDL的用量为0.08%,预聚反应温度为80℃,扩链反应温度为75℃,DMPA用量为6%,产物具有良好的水分散性。利用红外光谱(FT-IR)和热失重分析仪(TGA)对产物进行了表征,并用X射线衍射(XRD)分析了胶膜的结晶度,还对胶膜的耐水性能和拉伸强度进行了测试,结果表明,制备的树枝状水性聚氨酯的吸水率为12.1%,拉伸强度为16.2 MPa,热分解温度为205℃。

The polyurethane prepolymer was prepared in which the isophorone diisocyanate (IPDI),polycarbon-ate glycol (PCDL),diethanolamine (DEA),castor oil (C.O.)and 2,2-dimethylol propionic acid (DMPA)were as raw materials,the dibutyltin dilaurate(DBTDL)was as catalyst.The polyurethane prepolymer was grafted on 1 .0 generation of polyamide-amine (PAMAM),and then a new type of dendritic waterborne polyurethane was synthesized.The synthesis conditions were optimized by single factor analysis method.The optimum condi-tions were that the prepolymerization reaction temperature was 80 ℃,the temperature of chain extension reac-tion was 75 ℃,the dosage of DBTDL was 0.08% and the dosage of DMPA was 6%.The product took on good water dispersibility.The products were characterized by Fourier transform infrared spectroscopy (FT-IR)and thermogravimetric analysis (TGA),its crystallization degree was determined by XRD and the water resistance and tensile strength of the film were tested too.The results showed that its bibulous rate was 12.1%,the ten-sile strength was 16.2 MPa and the thermal decomposition temperature was 205 ℃.